BIOPURE Corporation has successfully manufactured a polymerized bovine hemoglobin solution which physiologically oxygenates as well as or better than red blood cells. Key performance characteristics include better 02/CO2 exchange at the cellular level than fresh human blood. The product is essentially free of endotoxins, phospholipids, clinically antigenic agents, plasma proteins, lipids or other potentially toxic substances. The product is stable while frozen at -20 degree C with a shelf life greater than six months The purpose of this SBIR is to use this substance, Hemopure 1, or its precursor, an unpolymerized monomer form, OXYPURE, to demonstrate further the applications of the material as a non- toxic, oxygen carrying perfusate in cardiac organ preservation prior to transplantation. Preliminary studies in small numbers of rabbits, dogs, sheep, and non-human primates have been successful and prove that these substances are biocompatable and serve as oxygen carriers. BIOPURE intends to perform more stringent studies which specifically demonstrate the value of one or both of these substances in cardiac organ preservation. The purpose of these studies as outlined in the research protocol section of the application will be to understand the physiological mechanisms involved and the performance characteristics of the material in organ preservation. The end goal of this research is to collect sufficient data to support a phase II grant designed to evaluate organ preservation time prior to transplantation in animals and possibly humans